Roots of a polynomial

You have entered the following polynomial roots
Entered expression
The resulting polynomial with given roots has the form
Entered expression

Description

Often in life a situation arises that is inverse to the problem of finding the roots of a polynomial of the form

Polynomial of one variable

where b,c....z,w are the coefficients of the polynomial.

When n=2 we get a quadratic equation

for n=3 cubic, etc.

This service allows you to solve the problem of finding such coefficients if the roots of this polynomial are known.

It seems like a simple task, but when creating a fourth-degree polynomial, calculating the elements of the polynomial is already quite difficult.

See for yourself.

Let's take a quadratic equation 

Quadratic equation

Let us know its roots  first root of a quadratic equation and Second root of a quadratic equation

Then  first element of the polynomial,    last element of the polynomial

It is calculated simply and, moreover, based on these two rules, you can calculate verbally (in your head) integer roots for integer elements of a quadratic equation.

You just need to factor it   coefficient c into two factors so that their sum is equal Multiplier b

These factors will be the roots of the quadratic equation.

Now consider the cubic equation

Cubic equation

Let us know its roots  first root of a quadratic equation ,  Second root of a quadratic equation and 

Then  

First element of the cubic equation

Second element of the cubic equation

Third element of the cubic equation

It's already more difficult. If we take a polynomial of degree 4 and higher, we will see that the complexity of calculating the elements of the polynomial increases in geometric progression.

It will be even more difficult if the known roots contain complex numbers.

It is to simplify such calculations that this bot was invented.

In the examples you will see how easily and simply the bot creates a polynomial of arbitrary degree using known roots.

Examples

Determine the coefficients of a polynomial when the following roots are known

1 2+i 2-i

You have entered the following polynomial roots
Entered expression
The resulting polynomial with given roots has the form
Entered expression
 
Where can this be useful? To create problems by teachers, so that students do not take information from various workbooks, but try to think on their own.
And also to create a polynomial of arbitrary degree if its roots are known.

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